Sound recording and reproducing device



Jan. 7, 1958 G. STEINEGGER 2,819,350

v SOUND RECORDING AND REPRODUCING DEVICE Filed Feb 27, 1956 v INVENTOR: C? ovcxmfl ve \n ease r United States Patent '0 SOUND RECORDING AND REPRODUCING DEVICE Giovanni Steinegger, Aurigeno, Switzerland Application February 27, 1956, Serial No. 568,088

Claims. (Cl. 179--100.2)

The present invention relates to a sound recording and reproducing device and more particularly to a drive mechanism adapted for use in sound recording and reproducing devices of the magnetized wire type, comprising two bobbins arranged side by side in the same plane and adapted to receive the steel wire influenced by a magnetic head arranged between the bobbins, and a driving motor arranged in such a way that the bobbins may selectively be driven in the one or the other direction.

According to the invention a drive mechanism is provided which comprises, in combination, a driving device mounted on the shaft of a driving motor tiltable to a certain angle, and arranged between two driving discs provided on the axle of one bobbin. These discs, depending upon the position of the driving device obtained by tilting of the motor, are contacted by this driving device and thus are selectively driven thereby, one of said driving discs being rigidly mounted on the axle of said one bobbin while the other of said driving discs is loosely i. e. freely rotatable thereon and connected with a pulley adapted to transmit its rotation at an increased speed onto a pulley connected with the axle of the other bobbin, so that driving the driving disc rigidly connected With the first bobbin serves for the spooling operation, while driving the driving disc loosely mounted on the axle of the first bobbin serves for the back spooling operation of the wire.

As during the winding on and off, respectively, the steel wire is displaced parallelly to itself according to the width of the bobbin, care must be taken that its relative position to the magnetic head is not changed.

This is attained in the present invention by the provision of means by which the magnetic head is moved together with the steel Wire in such a way that their relative position is not changed. For this purpose a worm wheel is arranged on the axle of the second bobbin which worm wheel drives a toothed wheel the shaft of which, over a heart-shaped disc, imparts to the magnetic head such a movement that the position of the latter corresponds at each moment to the position of the parallelly up and down moving steel wire, spring means providing for the contacting of this heart-shaped disc by the magnetic head.

Other features and advantages of the invention will become apparent from the description now to follow, of a preferred embodiment thereof given by way of example and in which reference will be made to the accompanying drawing showing, in a single figure, the arrangement of a drive mechanism according to the present invention.

In this figure reference numerals 1 and 2 designate the bobbins adapted to receive and discharge the steel wire designated by reference numeral 16. These bobbins 1 and 2 are arranged side by side in the same plane and there is arranged between them a magnetic head 11, which during the sound recording magnetizes the steel Wire. Spaced apart driving discs 6 anl 7, respectively,

a only a very short time. As soon as this back spooling is,

are arranged on the axle of bobbin 1, driving disc 6 being rigidly mounted on axle 18, while driving disc 7 is loosely mounted, i. e. freely rotatable thereon. In the space between the two driving discs 6 and 7 there is provided a driving device 5 driven by a motor 3 and constituted by a helical spring manufactured from a steel wire and coaxial with the motor shaft 3a.

The motor 3 is tiltable to a certain angle about a pivot 4 so that according to the direction of tilting the helical spring 5 comes into contact either with the driving disc 6 or with the driving disc 7. A pulley 8 is arranged on the hollow shaft 20 of driving disc 7, in the illustrated embodiment the upper side of this pulley 8 itself constituting the driving disc 7.

In order to render the transmission of the driving power of the motor onto the driving discs 6 and 7 reliable and in order to reduce to a minimum the wear and tear of the driving parts, the driving discs 6 and 7 are provided on their sides facing the driving spring 5 with a rubber covering vulcanized onto them and provided at the outer rim with an annular bead 6a and 7a, respectively. The helical spring 5 driven by the motor 3 bears, upon tilting of the motor about axle 4, either against the annular head of disc 6 or of disc 7 and rotates the disc contacted by the spring 5. It is desirable and advantageous to transmit the rotation of the driving disc 7 to bob,- bin 2 at an increased speed being a multiple of that of bobbin 1, this being obtained by means of a rope transmission 9 between pulley 8 and a smaller pulley 10 rigidly mounted on the axle 19 of bobbin 2. The speed may also be increased for example by choosing the diameter of driving disc 7 substantially smaller than the diameter of driving disc 6 since then with a certain speed of the motor the speed of the disc 7 is higher than the one of the disc 6 from the beginning. The pulley 10 driven at high speed by disc 7 and pulley 8, respectively, produces a rapid back spooling of the wire serving for the sound recording. The attained speed increase corresponds to the transmission ratio of the pulleys. The shaft 19 further carries a worm 12 engaged by a worm wheel 13 mounted on a shaft 14. The latter driven by the worm wheel 13 is provided at its other end with a disc 15 towards which the magnetic head is pressed under the action of a spring 17. For causing the magnetic head to follow the lateral movement of the steel wire 16 during the spooling and unspooling operations so that the relative position of the head 17 does not change with respect to the wire 16, the disc 15 has a heart-shaped cam surface, the spring 17 maintaining the magnetic head 11 in contact with said cam 15.

The described drive mechanism operates as follows: For the sound recording the motor 3 is tilted so that the helical spring 5 contacts the driving disc 6. The latter rotates bobbin 1 Winding up the steel wire 16 which, in turn rotates the bobbin 2. As thereby the steel Wire passes near the magnetic head 11 the latter will magnetize the,wire. The charge of the apparatus to sound reproducing must be preceded by a back spooling with the magnetic head disconnected. This back spooling is.

done at greater speed for time saving purposes. By tilting the motor 3 in the opposite direction the helical spring 5 connected with the motor shaft is brought into contact with the rubber bead 7a of driving disc 7 which is now rotated in the opposite direction. Accordingly the rotation of the bobbins 1 and 2 transmited to the latter by the rope transmission 8, 9, 10 is reversed with respect to the rotation during the recording and thus the steel wire is unspooled from bobbin 1 and Wound on bobbin 2. Owing to the relatively great transmission ratio of the rope transmission this back spooling necessitates- Patented Jan. 7, 19 58 terminated the direction of rotation may again be reversed by tilting the motor and the sound recorded onto the steel wire may be reproduced audibly.

The invention is of course not restricted to the transmission devices described and illustrated for transmitting the power of the motor to the driving discs in spite of the fact that the described embodiment has proved to be very reliable in operation. For example the helical spring may be replaced by a small rubber driving wheel connected with the motor shaft or by any other suitable transmission device known in the art.

I claim:

l. A sound recording and reproducing device of the wire type, comprising two bobbins mounted to rotate each with an axle and arranged side by side in the same plane, a steel wire adapted to be wound on and off said bobbins, a magnetic head arranged between said bobbins for magnetizing said steel wire, a driving motor tiltablc between two end positions for selectively rotating the bobbins in either direction, a pair of driving discs arranged in spaced relationship on the axle of one of said bobbins, one of said driving discs being rigidly mounted on said bobbin axle and the other of said driving discs being freely rotatable thereon, a first pulley connected for rotation with said last-mentioned driving disc, a second pulley rigidly mounted on the axle of the other bobbin, a rope transmission between said pulleys for transmitting rotation of the first pulley with increased speed to the second pulley and thus to the said other bobbin and driving means on the shaft of said motor extending between said pair of driving discs and adapted to contact, according to the tilting of the motor and thus of said driving means either one of the driving discs for selectively imparting rotation thereto.

2. A sound recording and reproducing device of the wire type, comprising two bobbins mounted to rotate each with an axle and arranged side by side in the same plane, a steel wire adapted to be wound on and off said bobbins, a magnetic head arranged between said bobbins for magnetizing said steel wire, a driving motor tiltable between two end positions for selectively rotating the bobbins in either direction, a pair of driving discs arranged in spaced relationship on the axle of one of said bobbins, a rubber covering wilcanized to the surface of each of said driving discs facing the other, an

annular rubber bead provided at the outer rim of said rubber covering on each of the driving discs, one of said driving discs being rigidly mounted on said bobbin axle and the other of said driving discs being freely rotatable thereon, a first pulley connected for rotation with said last-mentioned driving disc, 21 second pulley rigidly mounted on the axle of the other bobbin, a rope transmission between said pulleys for transmitting rotation of the first pulley with increased speed to the second pulley and thus to the said other bobbin, a helical spring made of steel wire and connected coaxially with the motor shaft for rotation therewith, said helical spring constituting a driving means extending between said pair of driving discs and adapted to frictionally engage, in one end position of tilting of the motor, the annular rubber head on the driving disc rigidly mounted on the bobbin axle for rotating same and in the other end position of tilting of the motor with the annular rubber bead on the other driving disc for transmitting over said rope transmission a reversed rotation at increased speed to the other of said bobbins.

3. A sound recording and reproducing device of the wire type, comprising two bobbins mounted to rotate each with an axle and arranged side by side in the same plane, a steel wire adapted to be wound on and off said bobbins, a magnetic head arranged between said bobbins for magnetizing said steel wire, a driving motor tiltable between two end positions for selectively rotating the bobbins in either direction, a pair of driving discs arranged in spaced relationship on the axle of one of 4 said bobbins, one of said driving discs being rigidly mounted on said bobbin axle and the other of said driving discs being freely rotatable thereon and forming a pulley, said freely mounted last-mentioned driving disc being of smaller diameter than the rigidly mounted firstmentioned driving discs, a pulley rigidly mounted on the axle of the other bobbin, a rope transmission between said pulleys for transmitting rotation of the first pulley to the second pulley and thus to said other bobbin, a rubber covering vulcanized to the surface of each of said driving discs facing the other, an annular rubber bead provided at the outer rim of said rubber covering on each of the driving discs, a helical spring made of steel wire and connected coaxially with the motor shaft for rotation thereof, said helical spring constituting a driving means extending between said pair of driving discs and adapted to frictionally engage, in one end position of tilting of the motor, the annular rubber bead on the driving disc rigidly mounted on the bobbin axle for rotating same and in the other end position of tilting of the motor with the annular rubber head on the other driving disc for transmitting over said rope transmission a. reversed rotation at increased speed to the other of said bobbins.

4.A sound recording and reproducing device of the wire type, comprising two bobbins mounted to rotate each with an axle and arranged side by side in the same plane, a steel wire adapted to be wound on and off said bobbins, a magnetic head arranged between said bobbins for magnetizing said steel wire, a driving motor tiltable between two end positions for selectively rotating the bobbins in either direction, means for moving the magnetic head with the parallelly moving steel wire so that the relative position of these two elements does not change, a pair of driving discs arranged in spaced relationship on the axle of one of said bobbins, one of said driving discs being rigidly mounted on said bobbin axle and the other of said driving discs being freely rotatable thereon, a first pulley connected for rotation with said last-mentioned driving disc, a second pulley rigidly mounted on the axle of the other bobbin, a rope transmission between said pulleys for transmitting rotation of the first pulley with increased speed to the second pulley and thus to the said other bobbin and driving means on the shaft of said motor extending between said pair of driving discs and adapted to contact, according to the tilting of the motor and thus of said driving means either one of the driving discs for selectively imparting rotation thereto.

5. A sound recording and reproducing device of the wire type, comprising two bobbins mounted to rotate each with an axle and arranged side by side in the same plane, a steel wire adapted to be Wound on and ofi said bobbins, a magnetic head arranged betwen said bobbins for magnetizing said steel wire, a driving motor tiltable between two end positions for selectively rotating the bobbins in either direction, a pair of driving discs arranged in spaced relationship on the axle of one of said bobbins, one of said driving discs being rigidly mounted on said bobbin axle and the other of said driving discs being freely rotatable thereon, a first pulley connected for rotation with said last-mentioned driving disc, a second pulley rigidly mounted on the axle of the other bobbin, a rope transmission between said pulleys for transmitting rotation of the first pulley with increased speed to the second pulley and thus to the said other bobbin and driving means on the shaft of said motor extending between said pair of driving discs and adapted to contact, accord ing to the tilting of the motor and thus of said driving means either one of the driving discs for selectively imparting rotation thereto, a worm wheel mounted on the axle of said second bobbin for rotation therewith, a toothed wheel cooperating with said worm wheel, a shaft driven by said toothed wheel, a heart-shaped cam disc mounted on said shaft for rotation therewith, spring means for maintaining said cam disc in operative con- 5 6 nection with the magnetic head for imparting to the latter, 1,638,999 Hornauer Aug. 16, 1927 upon rotation of the cam, a translatory up and down 1,731,235 Chipman Oct. 15, 1929 movement in accordance with the parallel displacement 2,468,453 Mallentjer Apr. 26, 1949 of the steel wire between the bobbins.

References Cited in the file of this patent UNITED STATES PATENTS 773,985 Ries Nov. 1, 1904 

